Volcanic ash

Balance's picture
Balance started the topic in Sunday, 12 Jul 2015 at 8:05pm

does anyones expertise in forecasting extend to having some insight into this weeks wind and weather in relation to the volcanic ash that is disrupting flights to Bali.

Due to fly there next week and getting very nervous.

I assumed winds this time of year would blow the ash west...but it doesnt seem to be happening...is it too high?

thermalben's picture
thermalben's picture
thermalben commented Monday, 13 Jul 2015 at 7:01am

It's the upper level winds (NW) that have been blowing the ash back towards Bali (not the surface level trades). Just had a quick scan of the charts and it looks like we'll see a slow improvement throughout the week although nor'westers may return later Thurs/Fri as another cold outbreak impacts the southern half of Australia. Too early to know about next week though (and it'll also depend on the status of the volcano too).

Balance's picture
Balance's picture
Balance commented Thursday, 16 Jul 2015 at 1:41pm

cheers Ben, appreciate the info. Have been trying to work this out for myself, so as not to hassle you...but I am pretty clueless. Jetstar are currently saying unfavourable winds may return later this week, as you said. Am due to fly Monday...anymore chrystal ball predictions would be gratefully received.

thermalben's picture
thermalben's picture
thermalben commented Thursday, 16 Jul 2015 at 2:47pm

The weekend looks a little dicey thanks to the upper level system across southern Australia (maintaining NW winds across eastern Indonesia), however it looks like we'll see a return to easterlies aloft from about late Monday or Tuesday onwards. So there's an outside chance Monday could still be affected but certainly from Tuesday onwards (at least for a few days through mid-next week) it's unlikely that the ash cloud will impact Denpasar. 

indo-dreaming's picture
indo-dreaming's picture
indo-dreaming commented Thursday, 16 Jul 2015 at 7:09pm

thermalben wrote:

It's the upper level winds (NW) that have been blowing the ash back towards Bali (not the surface level trades). Just had a quick scan of the charts and it looks like we'll see a slow improvement throughout the week although nor'westers may return later Thurs/Fri as another cold outbreak impacts the southern half of Australia. Too early to know about next week though (and it'll also depend on the status of the volcano too).

Okay now i get it, the whole time I've been wondering why it would be effecting Bali when the SE trades should be blowing steady…Cheers

Balance's picture
Balance's picture
Balance commented Sunday, 19 Jul 2015 at 10:07am

well theres been no further flight delays this week...did the predicted unfavourable conditions not eventuate...or has the actual volcano settled a bit.
I get on Jetstars site every chance I get, but they give no info on conditions or predictions at all, they havent posted an update since thursday evening...I am hoping thats a good thing, this time tomorrow I am hoping to be flying.
thanks again for your help Ben...and what site do you use to get your info...I have googled a heap of sites but I cant find anything useful?
I did find a satellite photo taken on the 12th, thought it was pretty cool...

http://www.abc.net.au/science/articles/2015/07/16/4274847.htm

thermalben's picture
thermalben's picture
thermalben commented Sunday, 19 Jul 2015 at 10:25am

Perhaps the volcano's output has eased back? I'm no expert on this kinda thing so I'm not sure. 

As for what source I use - just looking at 500hPa heights and winds across the eastern Indo region, available from any global forecasting site (such as Weatherzone).

crip's picture
crip's picture
crip commented Wednesday, 22 Jul 2015 at 1:09pm

I just saw that Virgin has cancelled flights in/out of Bali again, and Jetstar will be making a decision this arvo.
And now I'm getting a bit toey because we're heading over there in just under 1 month. I had expected (hoped) that the eruptions would have settled down by now.

Ben, I had a look at some 500hPa charts on Weatherzone & BOM but I couldn't see anything but easterlies, although I admit I found them a bit hard to read and therefore probably totally misreading them.

udo's picture
udo's picture
udo commented Wednesday, 22 Jul 2015 at 1:24pm

Anyone know if Perth direct to Lombok flights have been operating with the ash cloud ?

EDIT: that route got axed last year.

thermalben's picture
thermalben's picture
thermalben commented Wednesday, 22 Jul 2015 at 1:23pm

I'm a little stumped. Although winds through the lower-mid atmosphere (700/850/500) are only light in strength. However this is what's modeled, so perhaps local conditions are against model expectations? Sounding data (ie weather ballon trace) is unavailable from Denpasar Airport (from my usual sources).

thermalben's picture
thermalben's picture
thermalben commented Tuesday, 3 Nov 2015 at 1:41pm

Virgin has cancelled flights to and from Bali again.

http://www.abc.net.au/news/2015-11-03/virgin-australia-cancels-all-fligh...

mick-free's picture
mick-free's picture
mick-free commented Tuesday, 3 Nov 2015 at 2:29pm

Definitely got low level ash looking put window. She's pretty hazy out to the west and winds very light

Mick Free FIFOFOMO

wellymon's picture
wellymon's picture
wellymon commented Tuesday, 3 Nov 2015 at 4:41pm

put window?

That monkey is looking put mouth;)

Our brains are too small at the moment to comprehend the reality of what's happening in our forests . We're only just waking up so to speak . The big problem is we think we know everything, we are specks of dust on a timeline and we know nothing .